I'm not 100% sure what this is in English so I'll try to describe it. Gives that:(adsbygoogle = window.adsbygoogle || []).push({});

A: x^2 < 16

B: -4 < x

C: -4 < x < 4

I'm supposed to put out every possibility for => and <=> between A,B and C. The key says that A => B, A <=> C and C => B. I can understand this, but isn't it true for every proposition (I think that it's called this) that A <=> A. That is, every proposition implies itself?

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# Implications from propositions A => B, A <=> C and C => B

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